package com.ziJing.multithreading.sync.interview01;

import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.LockSupport;

/**
 * @program Multithreading
 * @description:
 * @author: zhangbo
 * @create: 2022/05/04 00:04
 */
public class T06_LockSupport {


    List<Object> list = Collections.synchronizedList(new LinkedList<>());


    int size() {
        return list.size();
    }


    void add(Object ele) {
        list.add(ele);
    }


    Object get(int index) {
        return list.get(index);
    }


    public static void main(String[] args) {

        T06_LockSupport c = new T06_LockSupport();


        Thread t2 = new Thread(() -> {
            System.out.println("t2 启动");
            if (c.size() != 5) {
                LockSupport.park();
            }

            System.out.println("t2 结束");

        }, "t2");

        t2.start();
        try {
            TimeUnit.SECONDS.sleep(1);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        Thread t1 = new Thread(() -> {
            System.out.println("t1 启动");
            for (int i = 0; i < 10; i++) {
                c.add(new Object());
                System.out.println("add " + i);

                if (c.size() == 5) {
                    LockSupport.unpark(t2);
                }

//              如果这里注释掉，会怎么样，怎么解决？
//              用两个 LockSupport
//                try {
//                    TimeUnit.SECONDS.sleep(1);
//                } catch (InterruptedException e) {
//                    e.printStackTrace();
//                }
            }

        }, "t1");

        t1.start();
    }
}
